Russia invaded Ukraine in February 2022 after issuing demands that it should never join the NATO alliance, starting a war that has caused hundreds of thousands of military and civilian casualties.
Mr Trump’s comments came after senior US and Russian diplomats met in Saudi Arabia for the first time in many years, to discuss ending the war. Ukraine and European nations were not represented at the talks. The US and Russia agreed to press ahead with negotiations to end the conflict.
Ukraine’s President President Volodymyr Zelenskyy said efforts to end the war must be "fair" and involve European countries including Turkey.
Reeta Chakrabarti presents BBC News at Ten reporting by Sarah Smith, Tom Bateman, James Waterhouse, Steve Rosenberg and Jonathan Beale.
Trump is a danger to world peace. – © Mark Alexander